Behind the scenes on Kimmel's big night (Power Players)This past weekend was what Washington, D.C. likes to call "nerd prom," more officially known as the White House Correspondents' Association's Dinner. Saturday's entertainment was none other than Jimmy Kimmel. Just before the big night, Kimmel opened up to ABC News' Jake Tapper about preparing the routine, lessons learned from past comedians, and deciding what is off limits for a crowd that includes the President of the United States and Kim Kardashian.